Weather in Rio De Janeiro in September 2025
Average weather
Average temperature in Rio De Janeiro in September
Going from a maximum of +38°C during the day to a minimum of +18°C during the night, the temperature in September averages around +30°C.
The average maximum temperature goes down 5% by the end of the month, compared with the beginning of the month, from +27°C to +26°C.
Is Rio De Janeiro warm or cold in September?
Rio De Janeiro is typically warm in September.
Maximum temperatures go up compared to the previous month from +25°C to +26°C. The minimum temperature also goes up from +18°C to +19°C.
It’s generally warm, but pack a long-sleeve shirt for evenings.
Take a look at how September is compared to other months in Rio De Janeiro:
Water temperature in Rio De Janeiro in September
Water in Rio De Janeiro in September is Comfortable. It varies from +20°C to +23°C, with an average of +21°C. This is almost similar to the air temperature, which averages +26°C.
The water temperature in September is one of the coldest of the entire year:
Can you swim in Rio De Janeiro in September?
Climate in Rio De Janeiro in September
| August | September | October | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +25°C | +26°C | +27°C | ||||
| Min. temperature | ||||||
| +13°C | +13°C | +16°C | ||||
| Max. temperature | ||||||
| +38°C | +38°C | +38°C | ||||
| Rainfall | ||||||
| 45 mm | 77 mm | 90 mm | ||||
| Wind | ||||||
| 2 m/s | 3 m/s | 3 m/s | ||||
| Avg. water temperature | ||||||
| +22°C | +21°C | +23°C | ||||
| Humidity | ||||||
| 76% | 77% | 78% | ||||
| Air pressure | ||||||
| 1018 HPa | 1016 HPa | 1014 HPa | ||||
| Sunny days | ||||||
| 13 | 9 | 6 | ||||
| Cloudy days | ||||||
| 7 | 6 | 7 | ||||
| Rainy days | ||||||
| 11 | 14 | 16 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
September weather is still as good as in August. It’s getting warmer as September arrives. The average maximum temperature goes up from +25°C to +26°C during the day. Prepare for more rain. Average rainfall goes from 45 mm to 77 mm. Humidity rises from 76% to 77%. Winds are stronger in comparison to August, going up from 2 m/s to 3 m/s on average. The days becoming less sunny, going from 13 sunny days in August to 9 in September.
Next month (October) brings a further decline in the weather.
Wind
The average wind speed is 3 m/s getting up to 5 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in Rio De Janeiro is gradually increasing during September, going from 3 m/s to 4 m/s over the course of the month.
Rain
How was the weather last September in Rio De Janeiro?
Climate Change over Years
The climate in Rio De Janeiro in September has not changed much over the last 43 years.
The average temperature was the lowest in 1989 (+26°C) and the highest in 2015 (+29°C). The driest year was 2001 with only 744 mm of rainfall, and the wettest year was 2019 with 2055 mm.
FAQ
Is September a good time to visit Rio De Janeiro?
Can you sunbathe in Rio De Janeiro in September?
Can you swim in Rio De Janeiro in September?
Is Rio De Janeiro rainy in September?
Is it sunny in Rio De Janeiro in September?
Other cities in Brazil
Monthly weather in Rio De Janeiro
Source of the data
For this page, we’ve looked at the typical weather in Rio De Janeiro, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.